OP, as he was popularly known in the media world, was 90 and is survived by his wife, a son and a daughter.
Regarded as an authority on India's nuclear programme and global nuclear issues, Sabherwal was born into a wealthy business family at Ludhiana on April 13, 1923.
After his graduation from Punjab University, Sabherwal moved to Kolkata where he led the undivided communist party's student and youth movement for the freedom of the country.